Hazards and Control of Risks in Artesanal Meat Products in Portugal

279 Pages·2012·1.84 MB·English

Hazards and Control of Risks in Artesanal Meat
Products in Portugal

Thesis submitted to the Universidade Católica Portuguesa, to attain
the
degree of PhD in Biotechnology with specialisation in Microbiology

by

Maria Isabel Pereira da Silva Campelos

July 2012

Hazards and Control of Risks in Artesanal Meat
Products in Portugal

Thesis submitted to the Universidade Católica Portuguesa, to attain
the
degree of Ph.D. in Biotechnology with specialisation in Microbiology

by

Maria Isabel Pereira da Silva Campelos

Under the supervision of Professor Paula Teixeira

Under the co-supervision of Professor Paul Gibbs

Under the co-supervision of Professor Tim Hogg

July 2012

―The known is finite, the unknown infinite; intellectually we stand
on an islet in the midst of an illimitable ocean of inexplicability. Our
business in every generation is to reclaim a little more
land.‖ Thomas Henry Huxley. 1884

―Remember that all models are wrong; the practical question is how
wrong do they have to be to not be useful‖. George Edward Pelham
Box, 1987

―The best model of a cat is another cat or, better, the cat itself‖,
Norbert Wiener, 1970

To my Father

General Introduction
GENERAL INTRODUCTION

―Salpicão de Vinhais‖ and ―Chouriça de Vinhais‖ are traditional dry-fermented
smoked meat sausages produced in the Vinhais, a small region of Trás-os-Montes.
These sausages are registered as Protected Geographical Indication (PGI) and are
a significant economic and cultural asset. The production of this kind of product is
mainly empirical, developed and perfected through centuries. The scientific
knowledge of this sausage variety is limited. Hence, the collection of sound,
scientific knowledge regarding its microbiological and chemical characteristics is
a necessity and a helpful tool for producers, retailers, official control agencies and
consumers, providing for much needed information regarding quality and food
safety.
Quantitative microbiological risk assessments aim at evaluating the risks, namely
the probabilities and severities of adverse health effects for consumers, resulting
from the exposure to pathogenic microorganisms present in foods, and
implementing appropriate management options. Governments need risk
assessment in order to select risk management measures for food trade at national
and international levels, avoiding risks to the population. But also, risk assessment
can be useful at production, at retailer, and at consumer levels.
This work aims to collect scientific data that could, partially, fill the gaps in
knowledge regarding these products, analyse the data and develop a risk-based
study, according to an internationally accepted framework and finally, to explore
the effect of hypothetical risk management measures on the safety of consumers,
regarding traditional dry fermented meat smoked sausages.
i
General Introduction
To perform a quantitative microbiological risk assessment, relevant data was
either extracted from experimental data and when this was not possible, from
relevant scientific literature. To perform the exposure assessment, a probabilistic
model was developed. Since the physico-chemical (intrinsic) characteristics of
the final product traditional dry fermented smoked sausages, fall near the
boundaries that allow, or not, growth of L. monocytogenes, a growth/no growth
equation, specific for the conditions of ―Salpicão‖ and ―Chouriça de Vinhais‖ was
developed to be included in the model. Though official organisations like the
European Food Safety Agency, state the relevance of growth/no growth
boundaries, few risk assessments incorporate this in their exposure assessment
models. Traditional dry fermented smoked sausages present low to medium risk to
the health of consumers. The use of more restrictive Performance Objectives
during processing and/or distribution will result in a further reduction of risk. A
more rigorous control of final product water activity and the use of a
bacteriocinogenic bioprotective culture during production may contribute
significantly to reducing the risk of listeriosis in consumers of these Traditional
Dry Fermented Smoked Sausages
ii